so let me get this straight.
Watchtower "new light" = baaaaaaaaaad
Mormon "new light = baaaaaaaaaaad
Scientific "new light" = gooooooood
I'll leave the discusion of the stupidity of applying the term "new light" to scientific discoveries to someone else...
Here's a difference you may be able to understand:
If A JW refuses to accept "new light", he is (in effect) told that Jesus Christ will slaughter him "soon" and until that day comes, his family is forbidden to even greet him under threat of the same punishment.
What is the penalty for refusing to accept scientific "new light"? Aside from advertising you insipidity for all the world to see, and the resulting mockery on internet discussion boards, that is....